Summary This application seeks to innovatively model the dynamic course of PTSD symptoms (PTSS), alcohol use disorder (AUD), and interpersonal conflict in a sample of 250 OIF/OEF/OND veterans and test hypotheses regarding combined effects of regulatory deficits, sleep disturbance, and the role of implicit approach / avoidance biases. Participants will be randomized to a cognitive bias modification (CBM) training condition in a 2 (Alcohol CBM, Control) x 2 (PTSD CBM, Control) design. The longitudinal burst design will result in a high fidelity dataset of near real-time assessments of AUD, PTSS, interpersonal conflict, and deficits in affect and behavior regulation over the course of 2 years. Sleep disturbance will be assessed by actigraphy. The application addresses three related questions. First, what processes link (PTSS), AUD symptoms, and interpersonal conflict at the within-person (i.e., daily) level? We propose that acute changes (e.g., day-to-day) in emotional and behavioral dysregulation are two pathways linking PTSS, AUD symptoms, and interpersonal conflict at the within-persons level. Second, what contributes to reciprocal associations between PTSS and AUD outcomes? Alcohol use has well-documented negative effects on sleep quality.1 Sleep disturbance is a common symptom of PTSD and impairs emotional and behavior regulation.2-7 Sleep disturbance may explain observed bi-directional associations. Third, why do state changes in emotional arousal and disinhibition increase symptoms of AUD reflecting impaired control over alcohol intake? Implicit response biases are conceptualized as a latent risk factor that influences behavior most strongly when self-regulation is impaired.8, 9 We propose that heightened emotional arousal and disinhibition associated with acute (i.e., daily) PTSS exacerbation result in an increased effect of implicit processes on behavior. Hence, effects of implicit biases on behavior vary across time and context. Heavy drinkers exhibit approach biases for alcohol 10-12 and sexual trauma victims exhibit avoidance biases toward trauma cues, which are related to PTSD severity.13 The experimental manipulation of implicit biases paired with the longitudinal burst design follow-up will test whether implicit response biases are related to PTSS and outcomes over time. We hypothesize that manipulating maladaptive response biases will reduce within-person associations between PTSS, affect and behavioral dysregulation, sleep disturbance, and the alcohol-related outcomes. The scientific premise of the application is bolstered by a well-informed and balanced review of the empirical literature and excellent pilot data supporting the hypotheses. The experimental design, multi-site sample, experience sampling protocol, and sophisticated data analytic strategy contribute to a highly rigorous test of the hypotheses. The proposed project integrates the study of implicit cognition, sleep disturbance, affect dysregulation, and behavioral disinhibition to advance understanding of functional associations between traumatic stress, AUD, and interpersonal conflict. This study will have high impact on the field?s understanding of mechanisms underlying PTSD and AUD comorbidity.